Heat the EVOO in a Dutch oven or chili pot over medium-high heat. Add the meat, then crumble and brown. Add the garlic, chiles, onions, ginger, chili powder, coriander, cumin, turmeric and some salt and pepper. Cook for 5 minutes, then add the tomato paste and stir a minute more. Add the stock and simmer for the flavors to combine, 15 to 20 minutes. Cool and store for a make-ahead meal.
Stir together the yogurt and Sriracha and store in a airtight container in the refrigerator.
When ready to eat, reheat the curry chili over medium heat, adding more stock or water if needed, while you bake the sweet potato fries.
For the fries: Place a rack in upper third of the oven and preheat to 450 degrees F. Cut the sweet potatoes into fairly thin fries, 1/4-inch thick, and arrange on baking sheet. Spray with the cooking spray and season with salt and pepper. Bake for 7 to 8 minutes, then switch on the broiler and broil until brown and crispy at edges, 15 to 20 minutes, turning once.
Melt the butter in a small skillet over medium heat. When it foams, add the garlic and swirl for a minute. Toss the fries with the butter and cilantro in large bowl using tongs.
To serve, arrange the fries on a platter or individual plates. Ladle the chili over the fries and top with the spicy yogurt, mint and scallions, and pass the limes for squeezing on top.